This invention relates to the field of rehabilitation devices and stretching devices in particular.
The plantar fascia is a sinuous band that attaches between the calcaneous bone of the heel and the metatarsals located in the front part of the human foot. Traumatic or, most often, chronic overstressing of this band leads to inflammation, as well as to tearing and shortening of the tissue through scarring. The resulting condition, which is commonly referred to as "plantar fasciitis", presents with mild to severe heel pain which, if left untreated, can interfere with walking and daily living activities, as well as athletic activity. This condition is diagnosed in both the athletic and sedentary population, and is especially common in the obese and in people who exercise on hard surfaces.
Non-surgical treatment of this condition often involves both anti-inflammatory agents (both systemic and topical) as well as lengthening the plantar fascia through a stretching routine designed to relieve the tension at the point of attachment to the heel.
Unfortunately, traditional active stretching techniques necessary to achieve an effective lengthening of the planter fascia, require more involvement and discipline than the average patient is likely to manifest. A device that can passively, comfortably and conveniently hold the foot in a developmental stretch while the patient sits or reclines would significantly increase compliance in a rehabilitation program and would perhaps alleviate the need for surgical intervention. Compliancy issues such as simplicity in applying and adjusting the device should be considered. In order to facilitate this developmental stretch, this device should be progressive, allowing for a variable amount of stretching, from mild to extreme, based on the patient's needs and foot structure. The ease of adjusting the intensity of the stretch will have relevancy as a compliancy issue. This device should also address the systemic nature of the plantar fascia, i.e., its interaction with the Achilles tendon and gastrocnemius muscle. It can be inferred that such a device would also be useful in addressing shortened length issues of the Achilles tendon and gastrocnemius muscle. Further, this device should be able to provide and customize the various components of a complete and effective stretch, i.e., dorsiflexion, toe bend, arch compression and gastrocnemius stretch. In addition, a device that is amenable to setting protocol and evaluating flexibility and flexibility gains would clearly have an advantage.
For such a common injury, there have been few attempts at providing a therapeutic device that could improve outcome, particularly by a developmental lengthening. There is a paucity of devices that will provide for all components of an effective stretch, i.e. dorsiflexion, toe bend, arch compression and gastrocnemius tensioning. Progressivity issues, compliance issues, quantification for protocol and evaluation issues have not been well developed in prior art.
Various orthoses, such as U.S. Pat. No. 5,665,059 to Klearman et al. and U.S. Pat. No. 5,486,157 to Dibendetto, while addressing an issue of dorsiflexion, can not provide either appropriate toe bend or arch compression. Such devices are not imbued with significant progressivity features nor are they amenable to quantifying the nature of a stretch for use in protocol. In fairness, this does not relate to the intended application of those types of devices.
U.S. Pat. No. 5,399,155 to Strassberg et al., described as a sock, and U.S. Pat. No. 5,776,090 to Bergmann et al., described as a splint, are designed merely to prevent contracture during long periods of inactivity and do not well address the various issues of developmental lengthening.
U.S. Pat. No. 5,358,469 to Patchel et al, described as a splint, while capable of addressing the issue of dorsiflexion and being a versatile device, is unable to provide all components of a stretch for plantar fascia. Again, in fairness, developmental lengthening of the plantar fascia is not the intended application for this device.
Exercisers such as U.S. Pat. No. 4,693,470 to Ogawa and U.S. Pat. No. 5,645,516 to Foster, while relating to dorsiflexion, are not by nature passive devices and also do not well address the various issues of developmental lengthening for planter fascia.